1. Field of the Invention
The present invention relates to an electric heating blanket and, more specifically, to a control circuit assembly for electric heating blanket, which consumes low voltage DC for working, controls the temperature of the electric heating blanket constantly within a limited range, and monitors the functioning of the electric heater.
2. Description of the Related Art
During the cold season or in cold weather areas, it is necessary to prepare stoves, electric heaters, electric heating blankets, and other warn-keeping apparatus for the sick persons, the children, the old persons, and the women. However, using a stove to burn fuel material for producing heat energy and light energy simultaneously produces toxic gas that is harmful to the health and the environment. Therefore, it is more practical to use an electric apparatus for warm-keeping. FIG. 1 illustrates a control circuit assembly for an electric heating blanket according to the prior art. The design of control circuit assembly comprises an electric heater 100 adapted for converting electric energy into heat energy, and a thermostat 200 adapted for regulating temperature. This design of control circuit assembly is functional, however it still has drawbacks as outlined hereinafter.
1. The electric heater 100 is controlled by the thermostat 200 to keep the temperature within a predetermined level. However, it the thermostat 200 fails to function well, the electric heater 100 may keep heating when the temperature surpassed the set value, resulting in a catastrophe.
2. The control circuit assembly has no display means for temperature indication. The user regulates the temperature subject to the sense of touch. It is inconvenient to a disable person to regulate the temperature of the electric heating blanket. In case the electric heater 100 fails, an accident may occur.
3. Because the control circuit assembly consumes AC power supply 300 and the electric heating blanket is to be covered on the user""s body, it is dangerous if the electric heating blanket is wetted or the control circuit assembly is short-circuited.
The present invention has been accomplished to provide an electric heating blanket control circuit assembly, which controls the temperature of the electric heater constantly within a limited range. It is another object of the present invention to provide an electric heating blanket control circuit assembly, which monitors the functioning of the main control circuit and, gives a warning signal when the main control circuit fails. According to one aspect of the present invention, the electric heating blanket control circuit assembly comprises a n electric heater, a sensor adapted for detecting the temperature level of the electric heater, a controller, the controller having a monitoring circuit adapted for monitoring normal functioning of the sensor and the electric heater and a main control circuit adapted controlling the operation of the electric heater subject to the detection result of the sensor to keep the temperature of the electric heater to be maintained within a limited range, and a power adapter adapted for providing low voltage DC to the electric heater, the sensor, and the controller for working. According to another aspect of the present invention, a display is provided and controlled by the controller for temperature and time display.